The present invention relates to an apparatus and method for use in handling sheet material articles and more specifically to an apparatus and method for feeding sheet material articles from a stack of sheet material articles.
Known devices for feeding sheet material articles from a stack of sheet material articles are disclosed in U.S. Pat. Nos. 3,650,525; 3,702,187 and 5,330,169. These devices include a suction applicator head which is movable to pull an edge portion of a lowermost sheet material article downward to form a gap between the lowermost sheet material article and the next adjacent sheet material article. A leading edge of a rotating separator disk is moved into the gap to further deflect the edge portion of the lowermost sheet material article so that it can be engaged by a feed drum. The feed drum pulls the sheet material article from the stack and deposits the sheet material article onto a collator conveyor.
There is a limited amount of time for the suction applicator head to pull the lowermost sheet material article downward to form a gap and for the rotating separator disk to move into the gap. In order to decrease the time required for the separator disk to move into the gap, the separator disk has previously been constructed with a relatively large outside diameter so that the periphery of the disk is moving at a high speed. Constructing the separator disk with a large outside diameter is frequently unacceptable due to space limitations. An alternative arrangement has been to rotate the separator disk so fast that it rotates through two complete revolutions each time a sheet material article is fed from the stack. This has the inherent drawback of allowing the lower sheet material article in the stack to droop downward in a manner which tends to promote misfeeding of sheet material articles and/or jamming of the leading edge portion of the separator disk against sheet material articles.
In the past, a single restrictor or support member has been used to support a corner portion of a stack of sheet material articles adjacent to the operator side of the stack. The lowermost sheet material article in the stack of sheet material articles is disengaged from the restrictor by the suction applicator head. A restrictor has not been provided at the opposite or feed corner portion of the stack of sheet material articles.